The present invention relates to an input device with a memory and a user interface, which comprises a display unit and a keyboard comprising several keys, which can be used to input text. Particularly the present invention relates to the editing of erroneous text on this device and a method for editing the erroneous text by using the input device.
A mobile communication unit is an example of an input device, which comprises a keyboard with a limited number of keys. In several mobile communication standards used presently it is possible to send a short textmessage from the user terminal or mobile communication unit to e.g. another mobile communication unit, which supports reception of such messages. The most common mobile communication units are hand-held mobile phones, a good example of which are Nokia 2110 and Nokia 6110 mobile phones. In addition to the keys reserved for starting a call and using menu functions, mobile phones often contain a familiar button-telephone-like keyboard with 12 keys arranged in matrix of four rows by three columns: numbers 1-9 and *, 0 and #. For writing of SMS-messages, most of the number keys (2-9, 0 and #) in Nokia 2110 mobile phone can be used to produce letters and other symbols. In this case, a part of the producible symbols reside xe2x80x9cunderxe2x80x9d each key, e.g. in order first three letters, then the number of the numeric keyboard and after these two or three special symbols. In this case a desired symbol is selected by pressing a key several times in a row without exceeding a certain period of time between presses. In this way it is possible to produce e.g. letter xe2x80x98Bxe2x80x99 by pressing number key 2 twice in a row. When continuing to write the word BART, the user is required to wait a while and then press number key 2 once to produce letter xe2x80x98Axe2x80x99. Then the user can continue and press number key 7 without waiting. The first press produces letter xe2x80x98Pxe2x80x99, a second press changes xe2x80x98Pxe2x80x99 to xe2x80x98Rxe2x80x99, which is now accepted by waiting a while or by continuing by inputting letter xe2x80x98Txe2x80x99 by pressing another number key. Letter xe2x80x98Txe2x80x99 is the first letter to be produced with number key 8, so it will be input with only one press of number key 8. To correct an error, a cursor is displayed on the display of the mobile phone in addition to the text, which cursor can be moved within the text and beside or under which a symbol can be removed by pressing correction key C. The presented method of writing an SMS-message is easy to learn, but using it is laborsome and slow.
To ease typing on a limited keyboard, several different probability-based or guessing systems have been developed to guess the words meant by the user, when he/she inputs text without specifying which letter of a given key he/she means when pressing that key. These systems are aimed to avoid or at least reduce the need for repeated keypresses. One probability-based system based on a statistical model to feed text has been presented in the patent publication GB 2 266 797 B, xe2x80x9cData Storage Apparatusxe2x80x9d. The publication presents a system, where e.g. a mobile phone searches its memory for such words, every symbol of which is included in partial sets of letters corresponding to different keys, selected by the user by pressing number keys. The phone selects the most probable word for an input word. Statistical methods can be used to significantly speed up the writing of an SMS-message, but the downside of their use is that they can guess the word totally wrong too. In this case it is possible that the second and fourth letter of a five-letter word have been guessed wrong, and the meaning of the word is thus totally altered. The editing function supported by the SMS composition function of the present mobile communication units would require the user to move the cursor to the correct location symbol by symbol, erase the erroneous symbol and input a correct symbol in a way familiar from e.g. Nokia 2110. Thus as the statistical method possibly produces several erroneous letters, the speed advantage of the statisticality is lost or at least a part of it is lost. While writing the user may also notice that e.g. a word should be added before the latest written word e.g. in English an article should be added or changed and thus add a new letter into the article preceding the word.
Now a method and means have been developed to edit input text, where a defined amount N of keys of a number keyboard of a telephone are arranged to correspond the same amount N of displayed symbols. By pressing one of these keys the user can select a symbol corresponding to that key as a correction point. Optionally the symbol at the correction point can be replaced with another symbol without a separate command from the user. Preferably, the said N displayed symbols are the N latest input symbols. Preferably the same keys of the number keyboard or a part of those keys that were used to input the text are used for this kind of targeting or optionally the targeting and the automatically following editing. Preferably the editing is started by shifting into a dedicated editing mode e.g by pressing a key provided for this purpose, normally not use for typing, e.g. the asterisk key (*). Preferably the editing mode is exited by pressing a certain key or after a defined time has elapsed from the last keypress. The advantage of an editing method according to the present invention is that an editing more efficient than the prior art is reached, because the cursor does not have to be moved by one single symbol at a time but its position can be selected as per the invention from N edited symbols by pressing one key that corresponds a desired new position of the cursor.
According to a first embodiment of the invention there is provided a method for editing input using an input device, which comprises a keyboard to input text and a display unit to display the input text, the method comprising the steps of:
displaying no more than a first number of symbols from the input text on the display unit grouped according to a first matrix,
grouping the said first number of keys of the keyboard to editing keys according to a defined second matrix;
defining a singular correlation, where every editing key corresponds to one position of a grouped symbol, between the symbols grouped according to said first matrix and the positions of the editing keys grouped according to said second matrix; and
selecting a position of a grouped symbol corresponding to an editing key as the editing position as a response to the use of the editing key, wherein the input device is a button telephone and the keyboard is the number keyboard of a telephone.
According to a first embodiment of the invention there is provided an input device, which has a keyboard to input text and a display unit to display the input text, which input device comprises
first means for displaying at most the first number of symbols from the input text grouped according to a first matrix on the display unit, wherein
said keyboard comprises a first number of keys grouped as editing keys according to a second matrix; and the input device further comprises:
means for defining a singular correlation, where each key corresponds to one position of a grouped symbol, between symbols grouped according to said first matrix; and editing keys grouped according to said second matrix;
means for selecting the position of the group symbol corresponding to the editing key as the editing position as a response to the use of an editing key wherein the input device is a button telephone and the keyboard is a telephone""s number keyboard.
In method for editing input text according to a second embodiment of the present invention as a response to a defined first command given with a certain key, a grouped symbol in an editing position is replaced with an other symbol from a symbol group of a basic key producing the grouped symbol, and as a response to a command given with an other certain key a new basic key is selected to replace the group of symbols changeable to the position of the symbol to be edited and the grouped symbol is replaced with one symbol from the symbol set of the new basic key.
A device according to a second embodiment of the present invention has been arranged as a response to a certain first manner use of a key to replace a grouped symbol in an editing position with an other symbol from the symbol set of the key that produces the grouped symbol, and as a response to a certain manner use of a key to read a next key as a new basic key and replace the edited symbol with one of the symbols input with the new basic key, i.e. one of the symbols under the basic key.
In method for editing input text according to a third embodiment of the present invention editing a grouped symbol in an editing position is allowed and after editing the grouped symbol in the editing position is replaced by a correcting symbol, for which correcting symbol a symbol that belongs to the same set as the symbol to be edited and most probably corrects the text to conform to a defined rule is selected.
In a third embodiment of the present invention the device allows editing of a symbol in an editing position and after the editing it is arranged to search for a probable word conforming to the editing and displaying it in place of the edited word. Preferably the user is also allowed to cancel the search of a probable word and return the pre-editing word.
In method for editing input text according to a fourth embodiment of the present invention replacing a symbol to be edited with another starts a search for the most probable word to replace the word in the input text that said symbol to be edited belonged to.
In a device according to a fourth embodiment of the present invention the search for a probable word following an editing is a default action that is always carried out after editing.
In method for editing input text according to a fifth embodiment of the present invention at least one probably incorrect symbol is searched from the symbols to be edited, and it is displayed in a manner differing from the other symbols to be edited. In this way the user is presented with a symbol, the correction of which is probably most profitable.
A device according to a fifth embodiment of the present invention is arranged to automatically search a probably incorrect symbol. A probably incorrect symbol is that symbol within the a text to be edited that most effects a selection of the symbols of the edited text and/or the replacing of which symbol most probably singularly points an originally meant word. The device is arranged to point out such a probably incorrect symbol preferably by displaying it in a way that differs from the other symbols displayed in the editing mode thus instructing the user to correct it first. In this manner the amount of editing needed can be minimized by starting editing with a change that most probably will lead to the correct word with one or the least number of changes, even if it had several misguessed symbols before entering the editing mode.
As a benefit of the present invention editing the input text becomes quicker as it is no longer necessary to move the cursor symbol by symbol to the erroneous symbols when editing the input text. The benefit is significant particularly when a limited keyboard is used and when editing a text recognised by statistical means. Another benefit of the present invention is that an editing method according to the present invention can well be used as an alternative to traditional editing methods. As a third benefit of the present invention, when using an editing method according to the invention, it is not necessary to allocate separate keys for moving the cursor, and so they can be left out and so save in the manufacturing cost of the device and/or manufacture a keyboard more efficient in its use of space. Preferably in this case a subsection of the keyboard, at least one key is reserved to scroll the text input during the editing mode in order to the browse the text to be edited in the editing mode. Furthermore an advantage of the embodiments 2 . . . 5 is that the selection of the symbol to be edited and replacing it with another symbol can be combined to occur simultaneously, thus further reducing the amount of keypresses needed.
Here the present invention has been described using a mobile communication unit and an SMS written on it as an example. The present invention can of course be applied to writing other text such as calendar or phonebook entries and to other devices than mobile communication units, e.g. PDA-devices (Personal Digital Assistant) with a limited keyboard, process automation devices, which cannot have a full-sized keyboard due to size, maintenance, special protection or other constraints, video games and vehicle computers, for the use of which only limited keyboard is available in e.g. the console of the car.